Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Postboks, 8905, Trondheim, Norway.
Department of Oncology, St. Olavs hospital, Trondheim University Hospital, Trondheim, Norway.
BMC Cancer. 2022 Nov 1;22(1):1117. doi: 10.1186/s12885-022-10194-2.
The aim of this prospective study was to investigate the prognostic value of metabolic tumor volume (MTV) and apparent diffusion coefficient (ADC) from baseline FDG PET/MRI compared to established clinical risk factors in terms of progression free survival (PFS) at 2 years in a cohort of diffuse large B-cell Lymphoma (DLBCL) and high-grade-B-cell lymphoma (HGBCL).
Thirty-three patients and their baseline PET/MRI examinations were included. Images were read by two pairs of nuclear medicine physicians and radiologists for defining lymphoma lesions. MTV was computed on PET, and up to six lymphoma target lesions with restricted diffusion was defined for each PET/MRI examination. Minimum ADC (ADC) and the corresponding mean ADC (ADC) from the target lesion with the lowest ADC were included in the analyses. For the combined PET/MRI parameters, the ratio between MTV and the target lesion with the lowest ADC (MTV/ADC and the corresponding ADC (MTV/ADC) was calculated for each patient. Clinical, histological, and PET/MRI parameters were compared between the treatment failure and treatment response group, while survival analyses for each variable was performed by using univariate Cox regression. In case of significant variables in the Cox regression analyses, Kaplan-Meier survival analyses with log-rank test was used to study the effect of the variables on PFS.
ECOC PS scale ≥2 (p = 0.05) and ADC (p = 0.05) were significantly different between the treatment failure group (n = 6) and those with treatment response (n = 27). Survival analyses showed that ADC was associated with PFS (p = 0.02, [HR 2.3 for 1 SD increase]), while combining MTV and ADC did not predict outcome. In addition, ECOG PS ≥2 (p = 0.01, [HR 13.3]) and histology of HGBCL (p = 0.02 [HR 7.6]) was significantly associated with PFS.
ADC derived from baseline MRI could be a prognostic imaging biomarker for DLBCL and HGBCL. Baseline staging with PET/MRI could therefore give supplementary prognostic information compared to today's standard PET/CT.
本前瞻性研究旨在探讨基线 FDG PET/MRI 的代谢肿瘤体积（MTV）和表观扩散系数（ADC）与既定临床危险因素相比，在弥漫性大 B 细胞淋巴瘤（DLBCL）和高级别 B 细胞淋巴瘤（HGBCL）患者中 2 年无进展生存（PFS）的预后价值。
纳入 33 例患者及其基线 PET/MRI 检查。由两组核医学医师和放射科医师对图像进行阅读，以定义淋巴瘤病变。在 PET 上计算 MTV，并为每次 PET/MRI 检查定义最多 6 个限制扩散的淋巴瘤靶病变。纳入靶病变中最小 ADC（ADCmin）和最低 ADC 对应的平均 ADC（ADCmean）进行分析。对于联合 PET/MRI 参数，计算每位患者 MTV 与最低 ADC 的比值（MTV/ADCmin 和相应的 ADC（MTV/ADCmean）。在治疗失败组（n=6）和治疗反应组（n=27）之间比较临床、组织学和 PET/MRI 参数，同时使用单变量 Cox 回归对每个变量进行生存分析。在 Cox 回归分析中具有显著差异的变量，使用 Kaplan-Meier 生存分析和对数秩检验研究变量对 PFS 的影响。
ECOC PS 量表≥2（p=0.05）和 ADC（p=0.05）在治疗失败组（n=6）和治疗反应组（n=27）之间存在显著差异。生存分析表明，ADC 与 PFS 相关（p=0.02，[HR 2.3 为 1 SD 增加]），而 MTV 和 ADC 的结合并不能预测结果。此外，ECOG PS≥2（p=0.01，[HR 13.3]）和 HGBCL 组织学（p=0.02 [HR 7.6]）与 PFS 显著相关。
MRI 基线 ADC 可能是 DLBCL 和 HGBCL 的预后成像生物标志物。与目前的标准 PET/CT 相比，基线 PET/MRI 分期可提供补充的预后信息。
